An example is given there. Uses ... , UniGUIJSUtils; procedure TMainmForm.UnimButton1Click(Sender: TObject); begin UnimCanvas1.JSInterface.JSCode('var me='#1'._cc_; if (me) {me.fillStyle="'+ uniColor2Web(clGreen, 1) +'"; me.font="20px sans-serif"; me.fillText("test", 100, 100)};'); end;